Does Allulose Make You Poop? Understanding Digestive Side Effects

January 1, 2026 •

4 min read

According to the Center for Science in the Public Interest, some studies have shown that consuming too much allulose can cause adverse gastrointestinal effects like diarrhea. The question, 'Does allulose make you poop?' is a valid one for those considering this low-calorie sweetener, and the answer lies in understanding how the body processes it.

Quick Summary

Allulose is poorly absorbed in the small intestine, and consuming excessive amounts can lead to gastrointestinal distress, including diarrhea, gas, and bloating, due to fermentation by gut bacteria.

Key Points

Dose-Dependent Effect: High consumption of allulose is the main trigger for digestive upset, including diarrhea and bloating, due to poor intestinal absorption.
Osmotic Action: The unabsorbed allulose in the large intestine pulls water into the bowel, which can lead to loose stools and a laxative-like effect.
Gut Fermentation: The fermentation of undigested allulose by gut bacteria is responsible for producing gas, contributing to bloating and discomfort.
Varying Tolerance: Individual sensitivity varies greatly, and people with conditions like IBS may experience symptoms at lower doses.
Moderation is Key: Starting with small amounts and gradually increasing intake is the best strategy to minimize potential gastrointestinal side effects.
Generally Safe: Allulose is recognized as safe by the FDA, but they have requested more research into its adverse gastrointestinal effects.

The Digestive Journey of Allulose

Allulose is a rare sugar, chemically similar to fructose but metabolized differently by the human body. Unlike regular sugar, which is readily absorbed and used for energy, allulose is absorbed only partially in the small intestine. Approximately 70% of the ingested allulose is absorbed and then excreted largely unchanged through urine within 24 hours. The remaining portion passes through to the large intestine, and it is this unabsorbed portion that can cause digestive issues, including causing you to poop.

The Mechanism Behind the Laxative Effect

The digestive effects of allulose, particularly diarrhea, are a result of two primary mechanisms:

Osmotic Effect: The unabsorbed allulose that reaches the large intestine is an osmotic substance, meaning it draws water into the bowel. This increased water content in the colon can lead to loose stools or diarrhea, especially when high doses are consumed.
Bacterial Fermentation: In the large intestine, gut bacteria ferment the undigested allulose. This fermentation process produces gases, which are responsible for side effects such as bloating and flatulence. The combination of increased water and gas pressure can lead to significant discomfort and a strong urge to have a bowel movement.

The Importance of Dosage and Individual Tolerance

The link between allulose and digestive upset is highly dependent on the dose consumed. For most individuals, small to moderate amounts of allulose are well-tolerated. However, as the dose increases, so does the risk and severity of gastrointestinal symptoms. Studies have established some guidelines for maximum intake to minimize these effects.

Single Dose Limit: A study involving healthy young adults suggested a maximum single dose of 0.4 g of allulose per kilogram of body weight to avoid GI symptoms. For a 150-pound (68 kg) person, this translates to about 27 grams, or roughly seven teaspoons, in one sitting. Consuming 0.5 g/kg or more significantly increased the risk of diarrhea in the study.
Daily Intake Limit: The same research indicated a maximum total daily intake of 0.9 g/kg body weight for regular ingestion. For the same 150-pound person, this is about 61 grams per day.

It is crucial to remember that these are average figures, and individual tolerance can vary dramatically. Factors such as pre-existing digestive conditions like Irritable Bowel Syndrome (IBS) can increase a person's sensitivity to allulose. The best approach is always to start with a very small amount and slowly increase intake over time to assess your body's personal tolerance.

Building Tolerance to Allulose

For some people, digestive discomfort might occur the first time they consume allulose, but their body may adapt with repeated, moderate exposure. Starting with just a small amount, like half a teaspoon in coffee or tea, can help gauge your reaction without overwhelming your system. This gradual approach allows your gut bacteria to adjust and may lead to fewer issues in the long run.

Allulose vs. Other Sweeteners

To better understand allulose's effects, it's helpful to compare it to other common sugar substitutes, particularly sugar alcohols, which are notorious for causing digestive distress.


Feature	Allulose	Erythritol	Xylitol	Sucralose	Table Sugar (Sucrose)
GI Symptoms	Dose-dependent; diarrhea, gas, bloating at high doses.	Can cause gas and bloating, often less severe than other sugar alcohols.	High risk of GI issues, especially diarrhea, due to poor absorption.	Generally well-tolerated; large amounts may affect gut microbiome in some.	No GI issues from poor absorption, but high intake can impact gut health and blood sugar.
Absorption Rate	Partially absorbed (approx. 70%).	Poorly absorbed, mostly excreted in urine.	Very poorly absorbed.	Poorly absorbed.	Fully absorbed and metabolized.
Laxative Effect	Possible at high doses.	Low risk compared to other sugar alcohols.	High risk.	Very low risk.	None from this mechanism.
Aftertaste	No off-tasting aftertaste for most users.	Sometimes described as having a cooling aftertaste.	No distinct aftertaste.	Some users report a bitter or metallic aftertaste.	None.

Practical Steps to Avoid Allulose-Related Digestive Issues

To enjoy allulose's sweet taste without the unwanted side effects, follow these practical strategies:

Start Small: Begin by using a small amount, such as half a teaspoon. This allows your digestive system to adapt without being overwhelmed.
Monitor Your Intake: Be mindful of your total allulose consumption throughout the day, especially from processed foods. Check nutrition labels on keto-friendly snacks, cereals, and baked goods.
Spread It Out: Instead of consuming a large amount in one sitting, distribute your allulose intake throughout the day in smaller portions.
Identify Your Threshold: Pay attention to how your body reacts to different amounts. You may find that your personal tolerance is lower than the amounts cited in studies.
Consider Other Ingredients: Be aware that allulose is often combined with other sweeteners, particularly erythritol. The combined effect could exacerbate GI symptoms.
Stay Hydrated: When consuming any poorly-absorbed sweetener, drinking plenty of water can help flush your system and mitigate some effects.

Conclusion

So, does allulose make you poop? Yes, it can, but it is not an inevitable outcome. The likelihood and severity of digestive issues like diarrhea and bloating are directly tied to the dose and your individual tolerance. By consuming allulose in moderation, starting with small amounts, and listening to your body's signals, most people can enjoy this low-calorie sweetener without significant gastrointestinal discomfort. Those with pre-existing digestive sensitivities should approach with extra caution. For safe use, adhering to recommended intake levels is the best practice for maintaining digestive comfort.

For more detailed information on allulose tolerance studies, you can refer to the National Institutes of Health resources.

Frequently Asked Questions

Excessive consumption of allulose can have a laxative effect for some sensitive individuals due to its poor absorption, which causes an osmotic action in the gut. However, it is not a laxative for everyone, especially when consumed in moderation.

Studies suggest that consuming a single dose exceeding 0.4 grams per kilogram of body weight can increase the risk of severe diarrhea. For an average 150-pound adult, this is roughly more than 27 grams in one sitting.

Allulose is poorly absorbed in the small intestine. The unabsorbed portion travels to the large intestine where it is fermented by gut bacteria, producing gases that lead to bloating and flatulence.

Yes, some evidence suggests that individuals may build up a tolerance to allulose over time. By starting with very small amounts and gradually increasing intake, your body can adjust to its digestive effects.

While allulose can cause GI issues, it is often better tolerated in moderate doses than some common sugar alcohols like xylitol, which are notorious for causing more significant digestive distress.

People with sensitive digestive systems or conditions like Irritable Bowel Syndrome (IBS) are more prone to experiencing GI side effects from allulose. They should exercise extra caution and may need to avoid it entirely.

While diarrhea is the more common GI side effect, a small number of people report experiencing constipation after consuming allulose. However, research focuses more on the laxative effect at higher doses.

The best approach is to start with a very small serving size, such as a single teaspoon, and see how your body reacts. You can then gradually increase the amount if you experience no negative side effects.